Housings have been provided with an interior cavity for receiving an electronic module wherein the housing provides mechanical protection for the module. Such housings may also protect the module from environmental contaminants by partially or substantially totally sealing the module within an interior housing cavity. If the module must dissipate a substantial amount of power, the housing may also have to provide a heatsink function or at least permit the module in the housing to be connected to a heatsink. Some prior housings have combined the protection and heatsink requirements by essentially constructing the housing in the form of a metal box configuration having one open side to permit mounting the module within the formed metal box.
A combined metal box housing and heatsink configuration, such as noted above, generally results in the housing have a substantial weight which may be undesirable in many applications. In addition, such a configuration also presents potential problems in providing external electrical access to the module contained within the housing while also sealing the module against external environmental containments. Also, when providing an all metal box type housing structure, care must be taken to avoid undesired electrical shorting of the module within the housing to the metal box sidewalls of the housing unless the metal box is made substantially larger than the electronic module. Increasing housing size to avoid this potential problem is undesirable since this will increase both the size and weight of the housing.
A prior art combined housing and heatsink configuration has been suggested which involves providing a heatsink block having convective cooling fins and then molding around a portion of this heatsink block four plastic sidewalls to define an interior module receiving cavity. This suggested structure is shown in FIGS. 1 and 2 of the present application. This prior structure provides a pair of plastic molded mounting ears having holes therethrough to provide for mounting the combined housing and heatsink structure. With regard to the combined housing and heatsink shown in FIGS. 1 and 2, while this structure substantially reduces the total weight of the housing which would be required for an all metal box type structure, the amount of heatsink capacity provided by this structure has been found to be somewhat limited since convective cooling fins provided as part of the heatsink block can provide only a limited amount of cooling for a module mounted within the housing. Also, it is necessary to accurately control the mounting torque when installing this type of housing to prevent cracking the plastic mounting ears of such a housing.
What is needed is an improved housing having heatsink capability which overcomes the above mentioned disadvantages of the prior housings.